1 files changed, 95 insertions, 69 deletions

diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index a1f918713006..83e03176819c 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -1,14 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *	common UDP/RAW code
  *	Linux INET6 implementation
  *
  *	Authors:
  *	Pedro Roque		<roque@di.fc.ul.pt>
- *
- *	This program is free software; you can redistribute it and/or
- *      modify it under the terms of the GNU General Public License
- *      as published by the Free Software Foundation; either version
- *      2 of the License, or (at your option) any later version.
  */
 
 #include <linux/capability.h>
@@ -23,6 +19,7 @@
 #include <linux/route.h>
 #include <linux/slab.h>
 #include <linux/export.h>
+#include <linux/icmp.h>
 
 #include <net/ipv6.h>
 #include <net/ndisc.h>
@@ -31,6 +28,7 @@
 #include <net/ip6_route.h>
 #include <net/tcp_states.h>
 #include <net/dsfield.h>
+#include <net/sock_reuseport.h>
 
 #include <linux/errqueue.h>
 #include <linux/uaccess.h>
@@ -40,29 +38,35 @@ static bool ipv6_mapped_addr_any(const struct in6_addr *a)
 	return ipv6_addr_v4mapped(a) && (a->s6_addr32[3] == 0);
 }
 
-static void ip6_datagram_flow_key_init(struct flowi6 *fl6, struct sock *sk)
+static void ip6_datagram_flow_key_init(struct flowi6 *fl6,
+				       const struct sock *sk)
 {
-	struct inet_sock *inet = inet_sk(sk);
-	struct ipv6_pinfo *np = inet6_sk(sk);
+	const struct inet_sock *inet = inet_sk(sk);
+	const struct ipv6_pinfo *np = inet6_sk(sk);
+	int oif = sk->sk_bound_dev_if;
 
 	memset(fl6, 0, sizeof(*fl6));
 	fl6->flowi6_proto = sk->sk_protocol;
 	fl6->daddr = sk->sk_v6_daddr;
 	fl6->saddr = np->saddr;
-	fl6->flowi6_oif = sk->sk_bound_dev_if;
 	fl6->flowi6_mark = sk->sk_mark;
 	fl6->fl6_dport = inet->inet_dport;
 	fl6->fl6_sport = inet->inet_sport;
-	fl6->flowlabel = np->flow_label;
-	fl6->flowi6_uid = sk->sk_uid;
+	fl6->flowlabel = ip6_make_flowinfo(np->tclass, np->flow_label);
+	fl6->flowi6_uid = sk_uid(sk);
 
-	if (!fl6->flowi6_oif)
-		fl6->flowi6_oif = np->sticky_pktinfo.ipi6_ifindex;
+	if (!oif)
+		oif = np->sticky_pktinfo.ipi6_ifindex;
 
-	if (!fl6->flowi6_oif && ipv6_addr_is_multicast(&fl6->daddr))
-		fl6->flowi6_oif = np->mcast_oif;
+	if (!oif) {
+		if (ipv6_addr_is_multicast(&fl6->daddr))
+			oif = READ_ONCE(np->mcast_oif);
+		else
+			oif = READ_ONCE(np->ucast_oif);
+	}
 
-	security_sk_classify_flow(sk, flowi6_to_flowi(fl6));
+	fl6->flowi6_oif = oif;
+	security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
 }
 
 int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
@@ -76,9 +80,10 @@ int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
 	struct flowi6 fl6;
 	int err = 0;
 
-	if (np->sndflow && (np->flow_label & IPV6_FLOWLABEL_MASK)) {
+	if (inet6_test_bit(SNDFLOW, sk) &&
+	    (np->flow_label & IPV6_FLOWLABEL_MASK)) {
 		flowlabel = fl6_sock_lookup(sk, np->flow_label);
-		if (!flowlabel)
+		if (IS_ERR(flowlabel))
 			return -EINVAL;
 	}
 	ip6_datagram_flow_key_init(&fl6, sk);
@@ -88,7 +93,7 @@ int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
 	final_p = fl6_update_dst(&fl6, opt, &final);
 	rcu_read_unlock();
 
-	dst = ip6_dst_lookup_flow(sk, &fl6, final_p);
+	dst = ip6_dst_lookup_flow(sock_net(sk), sk, &fl6, final_p);
 	if (IS_ERR(dst)) {
 		err = PTR_ERR(dst);
 		goto out;
@@ -106,14 +111,7 @@ int ip6_datagram_dst_update(struct sock *sk, bool fix_sk_saddr)
 		}
 	}
 
-	ip6_dst_store(sk, dst,
-		      ipv6_addr_equal(&fl6.daddr, &sk->sk_v6_daddr) ?
-		      &sk->sk_v6_daddr : NULL,
-#ifdef CONFIG_IPV6_SUBTREES
-		      ipv6_addr_equal(&fl6.saddr, &np->saddr) ?
-		      &np->saddr :
-#endif
-		      NULL);
+	ip6_sk_dst_store_flow(sk, dst, &fl6);
 
 out:
 	fl6_sock_release(flowlabel);
@@ -129,7 +127,7 @@ void ip6_datagram_release_cb(struct sock *sk)
 
 	rcu_read_lock();
 	dst = __sk_dst_get(sk);
-	if (!dst || !dst->obsolete ||
+	if (!dst || !READ_ONCE(dst->obsolete) ||
 	    dst->ops->check(dst, inet6_sk(sk)->dst_cookie)) {
 		rcu_read_unlock();
 		return;
@@ -140,19 +138,21 @@ void ip6_datagram_release_cb(struct sock *sk)
 }
 EXPORT_SYMBOL_GPL(ip6_datagram_release_cb);
 
-int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
+int __ip6_datagram_connect(struct sock *sk, struct sockaddr_unsized *uaddr,
 			   int addr_len)
 {
 	struct sockaddr_in6	*usin = (struct sockaddr_in6 *) uaddr;
 	struct inet_sock	*inet = inet_sk(sk);
 	struct ipv6_pinfo	*np = inet6_sk(sk);
-	struct in6_addr		*daddr;
+	struct in6_addr		*daddr, old_daddr;
+	__be32			fl6_flowlabel = 0;
+	__be32			old_fl6_flowlabel;
+	__be16			old_dport;
 	int			addr_type;
 	int			err;
-	__be32			fl6_flowlabel = 0;
 
 	if (usin->sin6_family == AF_INET) {
-		if (__ipv6_only_sock(sk))
+		if (ipv6_only_sock(sk))
 			return -EAFNOSUPPORT;
 		err = __ip4_datagram_connect(sk, uaddr, addr_len);
 		goto ipv4_connected;
@@ -164,7 +164,7 @@ int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
 	if (usin->sin6_family != AF_INET6)
 		return -EAFNOSUPPORT;
 
-	if (np->sndflow)
+	if (inet6_test_bit(SNDFLOW, sk))
 		fl6_flowlabel = usin->sin6_flowinfo & IPV6_FLOWINFO_MASK;
 
 	if (ipv6_addr_any(&usin->sin6_addr)) {
@@ -185,7 +185,7 @@ int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
 	if (addr_type & IPV6_ADDR_MAPPED) {
 		struct sockaddr_in sin;
 
-		if (__ipv6_only_sock(sk)) {
+		if (ipv6_only_sock(sk)) {
 			err = -ENETUNREACH;
 			goto out;
 		}
@@ -194,7 +194,7 @@ int __ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr,
 		sin.sin_port = usin->sin6_port;
 
 		err = __ip4_datagram_connect(sk,
-					     (struct sockaddr *) &sin,
+					     (struct sockaddr_unsized *)&sin,
 					     sizeof(sin));
 
 ipv4_connected:
@@ -221,16 +221,15 @@ ipv4_connected:
 	if (__ipv6_addr_needs_scope_id(addr_type)) {
 		if (addr_len >= sizeof(struct sockaddr_in6) &&
 		    usin->sin6_scope_id) {
-			if (sk->sk_bound_dev_if &&
-			    sk->sk_bound_dev_if != usin->sin6_scope_id) {
+			if (!sk_dev_equal_l3scope(sk, usin->sin6_scope_id)) {
 				err = -EINVAL;
 				goto out;
 			}
-			sk->sk_bound_dev_if = usin->sin6_scope_id;
+			WRITE_ONCE(sk->sk_bound_dev_if, usin->sin6_scope_id);
 		}
 
 		if (!sk->sk_bound_dev_if && (addr_type & IPV6_ADDR_MULTICAST))
-			sk->sk_bound_dev_if = np->mcast_oif;
+			WRITE_ONCE(sk->sk_bound_dev_if, READ_ONCE(np->mcast_oif));
 
 		/* Connect to link-local address requires an interface */
 		if (!sk->sk_bound_dev_if) {
@@ -239,9 +238,13 @@ ipv4_connected:
 		}
 	}
 
+	/* save the current peer information before updating it */
+	old_daddr = sk->sk_v6_daddr;
+	old_fl6_flowlabel = np->flow_label;
+	old_dport = inet->inet_dport;
+
 	sk->sk_v6_daddr = *daddr;
 	np->flow_label = fl6_flowlabel;
-
 	inet->inet_dport = usin->sin6_port;
 
 	/*
@@ -251,14 +254,16 @@ ipv4_connected:
 
 	err = ip6_datagram_dst_update(sk, true);
 	if (err) {
-		/* Reset daddr and dport so that udp_v6_early_demux()
-		 * fails to find this socket
+		/* Restore the socket peer info, to keep it consistent with
+		 * the old socket state
 		 */
-		memset(&sk->sk_v6_daddr, 0, sizeof(sk->sk_v6_daddr));
-		inet->inet_dport = 0;
+		sk->sk_v6_daddr = old_daddr;
+		np->flow_label = old_fl6_flowlabel;
+		inet->inet_dport = old_dport;
 		goto out;
 	}
 
+	reuseport_has_conns_set(sk);
 	sk->sk_state = TCP_ESTABLISHED;
 	sk_set_txhash(sk);
 out:
@@ -266,7 +271,7 @@ out:
 }
 EXPORT_SYMBOL_GPL(__ip6_datagram_connect);
 
-int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
+int ip6_datagram_connect(struct sock *sk, struct sockaddr_unsized *uaddr, int addr_len)
 {
 	int res;
 
@@ -277,7 +282,7 @@ int ip6_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 }
 EXPORT_SYMBOL_GPL(ip6_datagram_connect);
 
-int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
+int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr_unsized *uaddr,
 				 int addr_len)
 {
 	DECLARE_SOCKADDR(struct sockaddr_in6 *, sin6, uaddr);
@@ -287,14 +292,24 @@ int ip6_datagram_connect_v6_only(struct sock *sk, struct sockaddr *uaddr,
 }
 EXPORT_SYMBOL_GPL(ip6_datagram_connect_v6_only);
 
+static void ipv6_icmp_error_rfc4884(const struct sk_buff *skb,
+				    struct sock_ee_data_rfc4884 *out)
+{
+	switch (icmp6_hdr(skb)->icmp6_type) {
+	case ICMPV6_TIME_EXCEED:
+	case ICMPV6_DEST_UNREACH:
+		ip_icmp_error_rfc4884(skb, out, sizeof(struct icmp6hdr),
+				      icmp6_hdr(skb)->icmp6_datagram_len * 8);
+	}
+}
+
 void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 		     __be16 port, u32 info, u8 *payload)
 {
-	struct ipv6_pinfo *np  = inet6_sk(sk);
 	struct icmp6hdr *icmph = icmp6_hdr(skb);
 	struct sock_exterr_skb *serr;
 
-	if (!np->recverr)
+	if (!inet6_test_bit(RECVERR6, sk))
 		return;
 
 	skb = skb_clone(skb, GFP_ATOMIC);
@@ -316,20 +331,24 @@ void ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
 	serr->port = port;
 
 	__skb_pull(skb, payload - skb->data);
+
+	if (inet6_test_bit(RECVERR6_RFC4884, sk))
+		ipv6_icmp_error_rfc4884(skb, &serr->ee.ee_rfc4884);
+
 	skb_reset_transport_header(skb);
 
 	if (sock_queue_err_skb(sk, skb))
 		kfree_skb(skb);
 }
+EXPORT_SYMBOL_GPL(ipv6_icmp_error);
 
 void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
 {
-	const struct ipv6_pinfo *np = inet6_sk(sk);
 	struct sock_exterr_skb *serr;
 	struct ipv6hdr *iph;
 	struct sk_buff *skb;
 
-	if (!np->recverr)
+	if (!inet6_test_bit(RECVERR6, sk))
 		return;
 
 	skb = alloc_skb(sizeof(struct ipv6hdr), GFP_ATOMIC);
@@ -342,6 +361,7 @@ void ipv6_local_error(struct sock *sk, int err, struct flowi6 *fl6, u32 info)
 	skb_reset_network_header(skb);
 	iph = ipv6_hdr(skb);
 	iph->daddr = fl6->daddr;
+	ip6_flow_hdr(iph, 0, 0);
 
 	serr = SKB_EXT_ERR(skb);
 	serr->ee.ee_errno = err;
@@ -472,7 +492,7 @@ int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
 			const struct ipv6hdr *ip6h = container_of((struct in6_addr *)(nh + serr->addr_offset),
 								  struct ipv6hdr, daddr);
 			sin->sin6_addr = ip6h->daddr;
-			if (np->sndflow)
+			if (inet6_test_bit(SNDFLOW, sk))
 				sin->sin6_flowinfo = ip6_flowinfo(ip6h);
 			sin->sin6_scope_id =
 				ipv6_iface_scope_id(&sin->sin6_addr,
@@ -503,7 +523,7 @@ int ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len, int *addr_len)
 		} else {
 			ipv6_addr_set_v4mapped(ip_hdr(skb)->saddr,
 					       &sin->sin6_addr);
-			if (inet_sk(sk)->cmsg_flags)
+			if (inet_cmsg_flags(inet_sk(sk)))
 				ip_cmsg_recv(msg, skb);
 		}
 	}
@@ -701,14 +721,15 @@ void ip6_datagram_recv_specific_ctl(struct sock *sk, struct msghdr *msg,
 	}
 	if (np->rxopt.bits.rxorigdstaddr) {
 		struct sockaddr_in6 sin6;
-		__be16 *ports = (__be16 *) skb_transport_header(skb);
+		__be16 _ports[2], *ports;
 
-		if (skb_transport_offset(skb) + 4 <= (int)skb->len) {
+		ports = skb_header_pointer(skb, skb_transport_offset(skb),
+					   sizeof(_ports), &_ports);
+		if (ports) {
 			/* All current transport protocols have the port numbers in the
 			 * first four bytes of the transport header and this function is
 			 * written with this assumption in mind.
 			 */
-
 			sin6.sin6_family = AF_INET6;
 			sin6.sin6_addr = ipv6_hdr(skb)->daddr;
 			sin6.sin6_port = ports[1];
@@ -737,7 +758,7 @@ EXPORT_SYMBOL_GPL(ip6_datagram_recv_ctl);
 
 int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
 			  struct msghdr *msg, struct flowi6 *fl6,
-			  struct ipcm6_cookie *ipc6, struct sockcm_cookie *sockc)
+			  struct ipcm6_cookie *ipc6)
 {
 	struct in6_pktinfo *src_info;
 	struct cmsghdr *cmsg;
@@ -756,7 +777,7 @@ int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
 		}
 
 		if (cmsg->cmsg_level == SOL_SOCKET) {
-			err = __sock_cmsg_send(sk, msg, cmsg, sockc);
+			err = __sock_cmsg_send(sk, cmsg, &ipc6->sockc);
 			if (err)
 				return err;
 			continue;
@@ -770,6 +791,7 @@ int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
 		case IPV6_2292PKTINFO:
 		    {
 			struct net_device *dev = NULL;
+			int src_idx;
 
 			if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct in6_pktinfo))) {
 				err = -EINVAL;
@@ -777,12 +799,15 @@ int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
 			}
 
 			src_info = (struct in6_pktinfo *)CMSG_DATA(cmsg);
+			src_idx = src_info->ipi6_ifindex;
 
-			if (src_info->ipi6_ifindex) {
+			if (src_idx) {
 				if (fl6->flowi6_oif &&
-				    src_info->ipi6_ifindex != fl6->flowi6_oif)
+				    src_idx != fl6->flowi6_oif &&
+				    (READ_ONCE(sk->sk_bound_dev_if) != fl6->flowi6_oif ||
+				     !sk_dev_equal_l3scope(sk, src_idx)))
 					return -EINVAL;
-				fl6->flowi6_oif = src_info->ipi6_ifindex;
+				fl6->flowi6_oif = src_idx;
 			}
 
 			addr_type = __ipv6_addr_type(&src_info->ipi6_addr);
@@ -801,9 +826,10 @@ int ip6_datagram_send_ctl(struct net *net, struct sock *sk,
 
 			if (addr_type != IPV6_ADDR_ANY) {
 				int strict = __ipv6_addr_src_scope(addr_type) <= IPV6_ADDR_SCOPE_LINKLOCAL;
-				if (!(inet_sk(sk)->freebind || inet_sk(sk)->transparent) &&
-				    !ipv6_chk_addr(net, &src_info->ipi6_addr,
-						   strict ? dev : NULL, 0) &&
+				if (!ipv6_can_nonlocal_bind(net, inet_sk(sk)) &&
+				    !ipv6_chk_addr_and_flags(net, &src_info->ipi6_addr,
+							     dev, !strict, 0,
+							     IFA_F_TENTATIVE) &&
 				    !ipv6_chk_acast_addr_src(net, dev,
 							     &src_info->ipi6_addr))
 					err = -EINVAL;
@@ -1019,8 +1045,8 @@ exit_f:
 }
 EXPORT_SYMBOL_GPL(ip6_datagram_send_ctl);
 
-void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
-			     __u16 srcp, __u16 destp, int bucket)
+void __ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
+			       __u16 srcp, __u16 destp, int rqueue, int bucket)
 {
 	const struct in6_addr *dest, *src;
 
@@ -1028,7 +1054,7 @@ void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
 	src   = &sp->sk_v6_rcv_saddr;
 	seq_printf(seq,
 		   "%5d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "
-		   "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %d\n",
+		   "%02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u\n",
 		   bucket,
 		   src->s6_addr32[0], src->s6_addr32[1],
 		   src->s6_addr32[2], src->s6_addr32[3], srcp,
@@ -1036,11 +1062,11 @@ void ip6_dgram_sock_seq_show(struct seq_file *seq, struct sock *sp,
 		   dest->s6_addr32[2], dest->s6_addr32[3], destp,
 		   sp->sk_state,
 		   sk_wmem_alloc_get(sp),
-		   sk_rmem_alloc_get(sp),
+		   rqueue,
 		   0, 0L, 0,
-		   from_kuid_munged(seq_user_ns(seq), sock_i_uid(sp)),
+		   from_kuid_munged(seq_user_ns(seq), sk_uid(sp)),
 		   0,
 		   sock_i_ino(sp),
 		   refcount_read(&sp->sk_refcnt), sp,
-		   atomic_read(&sp->sk_drops));
+		   sk_drops_read(sp));
 }